JP2004223013A - Sewing machine lower feed mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the driving force necessary for vertical swing of a feed dog. <P>SOLUTION: A lower feed mechanism 10 of a sewing machine comprises a feed arm 20 with a head for supporting the feed dog 11 being so supported as to swing in a vertical direction and in a feeding direction, a feeding and rocking means 30 for rocking the feed arm along the feeding direction, and a vertical rocking means 40 for vertically rocking the feed arm 20. In the lower feed mechanism 10, an elliptic motion is applied to the feed dog by the feeding and rocking means and the vertical rocking means. The vertical rocking means is equipped with an arm member 46 which transmits force by the principle of leverage. The driving force for vertical swing is applied to the feed dog via the arm member. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lower feed mechanism, and more particularly, to a lower feed mechanism mounted on a sewing machine.
[0002]
[Prior art]
The conventional lower feed mechanism 100 of the sewing machine is provided with a saw-tooth-shaped tooth portion 101a on the upper end surface thereof. The feed tooth 101 is brought into contact with the fabric from below the needle plate and is fed in a predetermined feed direction. A feed arm 102 supported by the tip end and supported so that the tip end can swing in the vertical direction and the feed direction; feed swing means 110 for swinging the feed arm 102 in the feed direction; A vertical rocking means 120 for rocking the arm 102 in a vertical direction and a needle plate table 103 on which a needle plate 107 is mounted are provided on the upper surface thereof (for example, see Patent Document 1).
[0003]
As shown in FIG. 6, the feed arm 102 has a base end supported by a shaft member 104 disposed on a main body frame of the sewing machine (not shown) so as to be swingable about the vertical direction. On the other hand, as shown in FIG. 7, the shaft member 104 is provided so as to be able to move up and down with respect to the main body frame via the coil spring 105. It is possible to swing in the direction.
Further, the feed arm 102 is urged by a leaf spring 106 provided at a lower portion thereof to receive an elastic force downward.
[0004]
The feed dog 101 is arranged inside the needle plate base 103, and the state where the feed dog 101 is placed on the inner bottom surface of the needle plate base 103 by the above-mentioned leaf spring 106 is maintained. Further, needle plate base 103 is covered by needle plate 107 (see FIG. 9) from above. As a result, the feed dog 101 is located below the needle plate 107, but the needle plate 107 is provided with a window 107a at a position above the feed tooth 101, so that the feed arm 102 moves upward when the feed arm 102 swings. The movement causes the upper end of the feed dog 101 to protrude above the needle plate. At this time, the feed dog 101 simultaneously moves in the feed direction, so that the cloth on the needle plate 107 can be fed in the feed direction. .
[0005]
As shown in FIGS. 6 and 8, the feed rocking means 110 includes a reciprocating rocking horizontal feed shaft 111 and a pair of horizontal feed arms provided at one end of the horizontal feed shaft in a rocking radial direction. 112, a feed piece 113 supported at the tip of a pair of horizontal feed arms 112, and a receiving piece 115 provided at the tip of a rod 114 extending downward at a position near the tip of the feed arm 102. It is composed of
[0006]
The receiving piece 115 is formed in a substantially cubic shape, and is rotatably supported by a rod-shaped body 114 on the upper surface thereof. Then, the mutual arrangement of the sending piece 113 and the receiving piece 115 is set so as to enter the inside of the substantially U-shaped sending piece 113 when viewed from above.
Further, the feeding piece 113 has a convex peripheral surface formed on both side surfaces thereof, while a concave peripheral surface is formed at the tip of each horizontal feed arm 112. Then, since the feed piece 113 is supported by each horizontal feed arm 112 in a state where each peripheral surface of the feed piece 113 is in sliding contact with the peripheral surface of each horizontal feed arm 112, the horizontal feed shaft 111 swings. The feed piece 113 reciprocates in the feed direction via each horizontal feed arm 112, and further, the tip of the feed arm 102 reciprocates in the feed direction via the receiving piece 115 and the rod-shaped body 114. .
[0007]
As shown in FIGS. 6 and 9, the vertical swing means 120 includes a small gear 122 provided in the middle of a lower shaft 121 for driving the shuttle mechanism, and an internal gear 123a driven by the small gear 122. An upper and lower feed cam 123, an upper and lower feed pin 124 that contacts the eccentric peripheral surface of the upper and lower feed cam 123 and moves up and down, a housing 125 that rotatably stores the upper and lower feed cam 123, and a housing lid 126 are provided. ing.
[0008]
The vertical feed pin 124 is vertically movably supported by a through hole 103 a penetrating the inner bottom surface of the needle plate base 103, and the lower end surface thereof is in contact with the peripheral surface of the vertical feed cam 123.
The vertical feed cam 123 includes the internal gear 123a as described above, and the center line of the outer periphery is eccentric with respect to the center line of the internal gear 123a. Therefore, when the lower end surface of the vertical feed pin 124 slides on the outer peripheral surface of the vertical feed cam 123 driven by the small gear 122 in the housing 125, the vertical drive pin 124 periodically moves up and down. Become.
Further, the feed arm 102 is arranged above the vertical feed pin 124, and when the vertical feed pin 124 moves upward, the lower surface of the feed arm 102 comes into contact with the feed arm 102 to move up and down.
[0009]
In the conventional lower feed mechanism 100, the swing cycle of the feed rocking means 110 and the rocking cycle of the vertical rocking means 120 are phase-shifted so that the feed dog 101 moves in the feed direction at the same time as it moves upward. The cloth on the needle plate 107 is fed only in the feed direction.
[0010]
[Patent Document 1]
Japanese Patent No. 2959338 (FIG. 2)
[0011]
[Problems to be solved by the invention]
However, the above Patent Document 1 has a structure in which the vertical feed cam 123 is rotated by the small gear 122 provided on the lower shaft 121 to move the feed dog 101 up and down via the vertical feed pin 124. It was necessary to obtain a large driving force, and the burden was heavy. In particular, since the lower shaft 121 is mainly intended to rotationally drive the shuttle of the shuttle mechanism, an increase in the driving force for the vertical movement of the feed dog 101 may affect the operation of the shuttle. It was desired to reduce the burden.
[0012]
Further, the vertical feed pin 124 of the vertical rocking means 120 contacts the feed arm 102 with a small end surface of the pin to impart vertical movement, and the vertical feed pin 124 is perpendicular to the rocking feed arm 102. Since it only moves up and down, the up and down movement is applied in a point contact state, so that there has been a problem that the feed arm is bent or broken due to wear.
[0013]
Further, since the vertical feed cam 123 including the small gear 122 and the internal gear 123a of the vertical rocking means 120 is expensive, another alternative means has been desired.
In addition, if the swing in the feed direction and the swing in the vertical direction are not performed at the desired timing, the cloth feed amount does not reach the expected value, so it is necessary to adjust these timings. The meshing teeth of the small gear 122 of the moving means 120 and the internal gear 123a of the vertical feed cam 123 have to be shifted and changed, and there has been a problem that adjustment is complicated and difficult.
Further, in order to adjust the height of the feed dog 101, the upper and lower feed pins 124 have to be replaced with those having different heights, which makes the adjustment difficult and complicated.
[0014]
SUMMARY OF THE INVENTION It is an object of the present invention to reduce a driving force required for vertically swinging a feed dog. Further, the object is to prevent bending and breakage of the feed arm. Still another object is to reduce the cost of the apparatus. It is another object of the present invention to easily adjust the timing of the vertical swinging of the feed dog and the swinging of the feed direction, and to easily adjust the height of the feed dog.
[0015]
[Means for Solving the Problems]
According to the first aspect of the present invention, a feed arm which supports a feed dog at a tip end thereof and which tip end portion is swingably supported in a vertical direction and a feed direction, and swings the feed arm along the feed direction. Feed swinging means for moving the feed arm, and vertical swinging means for swinging the feed arm in the vertical direction, wherein the feed swinging means and the vertical swinging means impart an oval motion to the feed dog. , The vertical swing means has an arm member for transmitting a force based on the principle of leverage, and applies a driving force of vertical swing to the feed dog via the arm member.
[0016]
In the above configuration, the feed dog and the feed arm are rocked in the feed direction by the feed rocking means, and are rocked vertically by the vertical rocking means. The feed direction refers to the direction in which the cloth is fed during sewing. Therefore, by synchronizing each swinging means so that the feed dog moves upward and moves to the feed side of the fabric when it comes into contact with the fabric, the feed dog contacts the fabric in the feed direction while abutting against the lower surface of the fabric. Is transported.
[0017]
The invention according to claim 2 has the same configuration as the invention according to claim 1, and the vertical swinging means obtains a driving force for reciprocating swinging of the arm member from a lower shaft that drives the shuttle mechanism of the sewing machine. The configuration is adopted.
With the above configuration, the same effect as that of the first aspect of the invention is achieved, and the vertical swinging means swings the feed dog in the vertical direction by using the driving force obtained separately from the lower shaft.
[0018]
The invention according to claim 3 has the same configuration as the invention according to claim 1 or 2, and the up-and-down swing means is connected to a lower shaft, and a driven shaft to which rotational driving force is applied; And an eccentric cam that is rotatably driven and transmits a reciprocating swing driving force to the arm member. The eccentric cam is provided so that its eccentric position with respect to the driven shaft can be adjusted. I have.
[0019]
In the above configuration, the same operation as the first or second aspect of the invention is achieved, and the rotation of the driven shaft is reciprocated by the eccentric cam and transmitted to the arm member by the vertical swinging means.
Further, the eccentric cam can adjust the eccentric position with respect to the driven shaft. Here, the eccentric position adjustment refers to adjusting the rotation of the eccentric cam with respect to a driven shaft that is an eccentric shaft. Thereby, the phase of the vertical swinging operation of the feed dog with respect to the rotation of the driven shaft is adjusted. Therefore, the timing of the vertical swing of the feed dog and the swing of the feed direction can be adjusted.
[0020]
The invention according to claim 4 has the same configuration as the invention according to claim 1, 2, or 3, and the vertical swinging means moves up and down through a contact member provided with a contact surface for a feed dog or a feed arm. In addition to imparting swing in the direction, the contact member is supported so as to be able to change its posture following swing in the vertical direction of the feed dog or the feed arm.
[0021]
In the above configuration, the same effect as that of the first, second, or third aspect of the invention is exerted, and the contact surface is brought into contact with the feed dog or the feed arm, so that the contact member reduces the driving force of the vertical swing. Give. At this time, even if the contact surface with the contact surface causes an angle change due to the swing of the feed dog or the feed arm, the contact member can follow the change in posture and maintain the contact state.
[0022]
According to a fifth aspect of the present invention, there is provided the same configuration as the first, second, third, or fourth aspect of the present invention, and any one of a fulcrum, a force point, and an action point of the arm member can be rotationally adjusted. And an adjusting means for adjusting the height of the feed dog.
In the above configuration, the same operation as that of the first, second, third, or fourth aspect of the invention is achieved, and since the eccentric pin of the height adjusting means is eccentric, the eccentric pin is arranged horizontally and rotated. This makes it possible to change in the height direction at any of the fulcrum, the force point, and the action point of the arm member. Therefore, at any point of the arm member, a height change can be given to the feed dog by causing such a height change, and the feed dog is adjusted to a desired height by rotating the eccentric pin. I do.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
(Overall Configuration of Embodiment)
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an exploded perspective view of a lower feed mechanism 10 of the sewing machine according to the present embodiment. The lower feed mechanism 10 is mounted on, for example, a cylinder sewing machine, and feeds a cloth on a needle plate in a predetermined feed direction at a predetermined feed amount.
The lower feed mechanism 10 of the sewing machine is provided with a saw-toothed tooth portion 11a on the upper end surface thereof. The feed tooth 11 which comes into contact with the fabric from below the needle plate (not shown) and feeds the feed tooth in a predetermined feed direction; And a feed swinging means 30 for swinging the feed arm 20 in the feed direction, the feed arm 20 supporting the tip at the tip and swinging the tip in the vertical direction and the feed direction. A vertical swinging means 40 for swinging the feed arm 20 in the vertical direction, and a height adjusting means 50 for adjusting the position of the top dead center of the feed dog 11.
The direction along the cloth feeding direction on the horizontal plane is the X-axis direction, the direction orthogonal to the X-axis direction on the horizontal plane is the Y-axis direction, and the vertical up and down direction is the Z-axis direction. The Y-axis direction coincides with the longitudinal direction of the bed of the sewing machine (not shown).
[0024]
(Feed dog and feed arm)
The feed dog 11 is arranged below the needle plate with the tooth portion 11a inserted into a through hole provided in the needle plate. Then, when the upward movement by the vertical swing means 40 is performed via the feed arm 20, the tip of the tooth portion 11a protrudes from the upper surface of the needle plate, and at the same time, the movement in the feed direction by the feed swing means 30 is performed. Thus, the cloth is fed in the feed direction by contacting the lower surface of the cloth on the needle plate.
[0025]
The feed arm 20 supports the feed dog 11 at its distal end, and has its base end supported by an arm support 21, and is disposed in the bed of the sewing machine along the Y-axis direction.
The arm support 21 is rotatably supported about a Z-axis direction by a vertical axis T provided on a main body frame of a sewing machine (not shown), while the base end of the feed arm 20 is provided about an X-axis direction. It is rotatably supported. This allows the tip of the feed arm 20 to swing in the sewing machine along the Z-axis direction and the X-axis direction.
The feed arm 20 is provided with an elastic force by which a distal end of the feed arm 20 rotates downward by a spring (not shown).
[0026]
On the lower surface of the distal end portion of the feed arm 20, an up-down driving force applying section 22 serving as a receiving surface of the up-down moving piece 41 of the up-down swinging means 40 described later is formed. Further, on the lower surface of the feed arm 20 on the base end side of the vertical movement applying portion 22, a feed swing receiving member 36 of the feed swing means 30 described later is provided. The feed swing receiving member 36 is rotatably mounted on the feed arm 20 around the Z-axis direction.
[0027]
(Feed rocking means)
The feed swinging means 30 will be described with reference to FIGS. FIG. 2 is an explanatory view showing the feed swinging means 30 in a partial sectional view as seen from a line of sight along the Y-axis direction.
The feed rocking means 30 includes a feed rocking drive shaft 31 that performs reciprocating rocking within a fixed rotation angle range, and a tip portion of the feed rocking drive shaft 31 along with the feed rocking drive shaft 31 along the X-axis direction. The swinging piece 35 that swings by swinging, and the above-described feed swinging receiver 36 to which the swinging driving force is applied from the swinging piece 35 are provided.
[0028]
The feed swing drive shaft 31 is branched at its base end from an upper shaft (not shown) of the sewing machine (shaft for applying a vertical drive force to the sewing needle) and is provided with a drive force for the swing thereof. . For this purpose, a passive arm 32 is fixedly provided at the base end of the feed swing drive shaft 31 so as to extend in the swing radial direction. The passive arm 32 swings on the feed swing drive shaft 31 by being connected to the distal end of a rotatably supported connecting rod, for example, via an eccentric cam fixed to the upper shaft. Of driving force for the purpose. The swing cycle of the feed swing drive shaft 31 matches the rotation cycle of the upper shaft.
Further, the feed swing drive shaft 31 is fixedly provided at one end thereof with a pair of swing arms 33 and 34 extending in the swing radial direction adjacent to the feed swing drive shaft along the longitudinal direction thereof. . The pair of rocking arms 33 and 34 support a rocking piece 35 between its distal ends so as to be rockable about the Y-axis direction.
[0029]
The swing piece 35 has a rectangular parallelepiped shape. The feed rocking receiver 36 is formed in a U-shape supported by the feed arm 20 with the opening directed downward, and the rocker 35 is inserted into the U-shape with the rocker 35 inserted therein. Upon receiving the bidirectional pressing force along the X-axis direction, the distal end of the feed arm 20 swings along the feed direction.
The feed swing receiver 36 has a rotation support shaft 37 inserted in a through hole 23 provided in the feed arm 20 at an upper portion thereof, and the feed arm can rotate around the Z-axis direction. 20 supported. Therefore, even if the feed arm 20 swings in the feed direction, the feed swing receiver 36 rotates about the rotation support shaft with respect to the feed arm 20, and the inner surface of the feed swing receiver 36. The state of surface contact between the swinging piece 35 and both side faces of the swing piece 35 is effectively maintained.
[0030]
Further, when the swing piece 35 swings, a displacement along the Z-axis direction occurs to draw a locus of an arc centered on the feed swing drive shaft 31, but the feed swing receiver 36 is Because of the U-shape, there is a space above and below the rocking piece 35. Therefore, the swing piece 35 slides in the vertical direction inside the feed swing receiver 36, and only the driving force of the swing along the X-axis direction is transmitted to the feed swing receiver 36 side. Is done. The feed arm 20 swings up and down by the vertical swing means 40. At this time, the swing piece 35 slides up and down inside the feed swing receiver 36, so that the feed arm 20 is Even when vertical swinging is performed, it is possible to simultaneously transmit the driving force for swinging in the feed direction. Therefore, the depth of the feed swing receiver 36 is set to be deeper than the vertical stroke by the vertical swing means 40.
[0031]
(Vertical rocking means)
The vertical swing means 40 will be described with reference to FIGS. FIG. 3 is an explanatory view for explaining the swinging operation of the vertical swinging means 40, and FIG. 4 is an explanatory view showing a change in the attitude of the vertically movable piece 41 of the vertical swinging means 40.
The vertical movement means 40 is provided with a driven shaft 42 to which a rotational driving force is applied from the lower shaft 12 that rotationally drives the shuttle of the shuttle mechanism (not shown) of the sewing machine, and converts the rotational force of the driven shaft 42 into a reciprocating swing driving force. A cam mechanism 43, an arm member 46 as a lever which is provided with a reciprocating swinging driving force from the cam mechanism 43 to one end thereof to perform a swing operation as a whole, and supported by the other end of the arm member 46. A vertical moving piece 41 is provided as a contact member that swings along the vertical direction and applies a vertical swing driving force to the distal end of the feed arm 20.
[0032]
The lower shaft 12 is rotatably supported by the main body frame of the sewing machine in a state along the Y-axis direction, and is rotated at the same cycle as the upper shaft by applying a rotational driving force from the upper shaft via a timing belt. I do.
The driven shaft 42 is rotatably supported by the main body frame of the sewing machine along the X-axis direction, and is driven by a helical gear 47 that meshes with the helical gear 13 provided on the lower shaft 12. Is transmitted.
[0033]
A cam mechanism 43 is provided at one end of the driven shaft 42. The cam mechanism 43 has a short cylindrical shape and is eccentrically mounted on the driven shaft 42 at a position eccentric from the center thereof. The cam mechanism 43 is rotatably mounted along the outer periphery of the eccentric cam member 44. Cylindrical body 45. A pair of arm portions 45a are protruded from the upper portion of the cylindrical body 45 in a row in the X-axis direction, and a height adjusting means 50 described later is provided between the arm portions 45a at one end of the arm member 46. One end of the arm member 46 is connected rotatably about the X-axis direction via the arm member 46. Therefore, as shown in FIG. 3, only the vertical displacement by the eccentric cam member 44 is transmitted to one end of the arm member 46 by the rotation of the driven shaft 42 by the cam mechanism 43.
[0034]
The arm member 46 is swingably supported by the main body frame via a pivot pin 47 along the X-axis direction at an intermediate position in the longitudinal direction substantially along the Y-axis direction. As described above, one end of the arm member 46 is provided with a vertical swing driving force by the cam mechanism 43, and the other end supports the vertical moving piece 41. In the arm member 46, the support position (fulcrum) is set at a position closer to the output position (operating point) than the input position (power point) of the driving force by the pivot pin 47, and the driving force is small according to the principle of leverage. This allows the vertical moving piece 41 to move up and down.
[0035]
Further, the vertical moving piece 41 is supported at the other end of the arm member 46 by a support shaft 48 extending in the X-axis direction. Therefore, even in the vertical swing of the arm member 46 and the swing of the feed arm 20, the contact surface, which is the upper surface of the vertical moving piece 41, is formed on the lower surface of the vertical drive force applying portion 22 of the feed arm 20. It is possible to follow the change and maintain the surface contact state at all times. Accordingly, it is possible to effectively suppress the bending of the feed arm 20 due to the contact or the wear due to the small area.
When the feed arm 20 swings along the X-axis direction, the upper surface of the vertical moving piece 41 slides with respect to the lower surface of the vertical drive force applying portion 22 of the feed arm 20, and the X-axis of the feed arm 20 Does not hinder the swinging motion along the direction.
[0036]
Further, the cam member 44 of the cam mechanism 43 described above is fixed to the driven shaft 42 by screwing (not shown), and by loosening such a screw, the cam member 44 is rotated with respect to the driven shaft 42. The eccentric position can be adjusted. Accordingly, only the phase of the vertical movement of the feed arm 20 and the feed dog 11 via the arm member 46 and the vertical moving piece 41 can be adjusted without changing the cycle, and the feed direction of the feed arm 20 and the feed tooth 11 can be adjusted. It is possible to adjust the timing of the top dead center position with respect to the swing.
[0037]
(Height adjustment means)
The height adjusting means 50 will be described with reference to FIGS. 5A is an enlarged view of the height adjusting means 5, and FIG. 5B is a cross-sectional view taken along line XX of FIG. 5A.
The height adjusting means 50 includes an eccentric pin 51 inserted into a through hole 45b provided in each arm 45a of the cylindrical body 45 along the X-axis direction, and an external eccentric provided on each arm 45a. And a blind screw 52 screwed into a screw hole 45c inserted into the through hole 45b.
[0038]
The eccentric pin 51 has both ends set to have an outer diameter that can be inserted into the through hole 45b, and the middle part has a smaller diameter than the both ends. Further, the small-diameter portion and the large-diameter portion are connected in a state where the center line of the small-diameter portion is eccentric with respect to the center lines of the large-diameter portions at both ends. As shown in FIG. 1, the one large-diameter portion is separable from the small-diameter portion. In this state, the small-diameter portion is inserted into an engagement hole provided at one end of the arm member 46, and a cam mechanism is provided. 43 and the arm member 46 are connected.
Further, each blind screw 52 prevents the eccentric pin 51 from dropping out of the through hole 45b and also prevents the eccentric pin 51 from rotating inside the through hole 45b.
[0039]
Since the small-diameter portion moves by rotating the eccentric pin 51 in the through hole 45b, the height adjusting means 50 changes the height of one end of the arm member 46 connected to the small-diameter portion. Can be. Further, the height of the vertical moving piece 41 at the other end of the arm member 46 changes as the height of the one end of the arm member 46 changes. Therefore, by rotating the eccentric pin 51, the vertical swing range of the feed arm 20 and the feed dog 11 at the time of vertical swing through the vertical moving piece 41, and furthermore, the height of the top dead center can be adjusted. After the height adjustment, it is necessary to fasten each blind screw 52 and fix the eccentric pin 51.
[0040]
(Description of operation of the embodiment)
In the lower feed mechanism 10 of the sewing machine having the above configuration, when the upper shaft of the sewing machine starts rotating, the lower shaft 12 and the driven shaft of the vertical swing means 40 start rotating at the same rotation speed. As a result, the cam mechanism 43 swings the arm member 46, and the feed arm 20 and the feed tooth 11 move in the vertical direction at the same cycle as the vertical movement of the sewing needle via the vertical moving piece 41 at the distal end of the arm member 46. Rocks.
On the other hand, with the start of rotation of the upper shaft, the feed rocking drive shaft 31 rocks at the same frequency as the rotation speed of the upper shaft, and the feed arm 20 and the feed dog via the rocker 35 and the feed rocker receiver 36. Numeral 11 swings in the feed direction at the same period as the swing in the vertical direction.
Therefore, the feed arm 20 and the feed dog 11 simultaneously swing up and down and swing in the feed direction. At this time, by adjusting the rotational angle position of the cam member 44 of the cam mechanism 43 so that they act in a predetermined phase, the feed dog 11 performs a motion that draws an elliptical trajectory. Further, by adjusting the upper end of the tooth portion 11a of the feed dog 11 so as to protrude from the through hole of the needle plate when moving in the feed direction, the cloth on the needle plate can be fed in the feed direction. .
Further, the cloth feed amount can be adjusted by adjusting the height of the feed dog 11, so that the eccentric pin 51 can be rotationally adjusted by the height adjusting means 50 and set to a predetermined feed amount.
[0041]
(Effects of the embodiment)
In the lower feed mechanism 10, since the arm member 46 of the vertical rocking means 40 uses the lever principle, the power supply source can perform the vertical rocking of the feed arm 20 and the feed dog 11 with a small driving force. Becomes possible. In particular, since the vertically swinging means 40 branches from the lower shaft 12 that supplies the power of the shuttle mechanism and receives the driving force, the above-described effect reduces the possibility of affecting the rotating operation of the shuttle of the shuttle mechanism, Ensures stable operation of the hook mechanism.
[0042]
It goes without saying that the lower feed mechanism 10 may be applied not only to the cylinder bed sewing machine but also to other types of sewing machines as long as it performs cloth feeding.
Further, the eccentric pin 51 of the height adjusting means 50 supports the position to be the point of force of the arm member 46, but may be configured to support the fulcrum or the point of action.
[0043]
【The invention's effect】
According to the first aspect of the present invention, the vertical swing means transmits the driving force of the vertical swing by the arm member acting as a lever, so that the fulcrum position is set closer to the power supply side than the power supply source. This makes it possible to move the feed dog up and down with a small driving force.
Also, unlike the related art, an eccentric cam member having a small gear and an internal gear is not required, and an arm member which is a simple rod-shaped member is used. Therefore, the cost of parts is reduced and the productivity of the apparatus is improved. It becomes possible.
[0044]
According to the second aspect of the present invention, since the vertical swinging means branches from the lower shaft for supplying the power of the shuttle mechanism and receives the driving force, an independent drive source is not required and the synchronization with the operation of the shuttle is facilitated. It becomes possible to aim at.
Further, since the present invention enables the vertical swinging operation of the feed dog to be performed with a small driving force, the possibility of affecting the rotating operation of the shuttle mechanism of the shuttle mechanism is reduced, and the stable operation of the shuttle mechanism is reduced. Guarantee.
[0045]
According to the third aspect of the present invention, since the eccentric cam can adjust the eccentric position with respect to the driven shaft, the phase of the vertical movement of the feed dog with respect to the rotation of the driven shaft is adjusted, and It is possible to adjust the timing between the vertical swing of the teeth and the swing in the feed direction.
Also, unlike the related art, there is no need to change the position of the meshing teeth of the small gear and the internal gear, and only the rotation of the eccentric cam can be adjusted. And the timing of swinging in the feed direction can be adjusted.
[0046]
According to the fourth aspect of the invention, since the driving force of the vertical swing is transmitted to the feed arm or the feed dog by the contact member having the contact surface, the case where the driving force is applied with a small area as in the related art is provided. In contrast, it is possible to effectively avoid the occurrence of bending deformation, abrasion, and chipping of the feed arm and the feed dog. In particular, since the contact member can change its posture, it keeps the surface contact state by following the swing of the feed arm or feed dog, and it is possible to prevent further occurrence of bending deformation, wear, and loss It is.
[0047]
According to the fifth aspect of the present invention, since the eccentric pin that can be rotated is provided at any one of the fulcrum, the force point, and the action point of the arm member, the height of the feed dog can be adjusted by the rotation operation. In addition, it is possible to easily adjust the height of the feed dog with a simple configuration without having to replace pins as in the related art.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a lower feed mechanism of a sewing machine according to an embodiment.
FIG. 2 is an explanatory diagram showing a partial cross-sectional view of the feed rocking means disclosed in FIG. 1 viewed from a line of sight along a Y-axis direction.
FIG. 3 is an explanatory diagram illustrating a swing operation of a vertical swing unit.
FIG. 4 is an explanatory diagram showing a change in posture of a vertically moving piece included in the vertically swinging means.
5 (A) is an enlarged view of the height adjusting means 5, and FIG. 5 (B) is a sectional view taken along line XX of FIG. 5 (A).
FIG. 6 is an exploded perspective view of a conventional lower feed mechanism of the sewing machine.
FIG. 7 is an explanatory view showing a support state of the shaft member shown in FIG. 6;
FIG. 8 is an explanatory diagram of the feed swinging unit shown in FIG. 6 as viewed from a line of sight along a horizontal feed axis.
FIG. 9 is an explanatory view of the up-and-down swing unit shown in FIG. 6 as seen from a line of sight along a lower axis.
[Explanation of symbols]
10 Lower feed mechanism
11 feed dog
12 Lower shaft
20 feed arm
30 Feed swing means
40 Vertical swing means
41 Vertical moving piece (contact member)
42 driven shaft
44 Eccentric cam member (eccentric cam)
46 Arm member
50 Height adjustment means (adjustment means)
51 Eccentric pin

Claims (5)

A feed arm that supports the feed dog at its tip and the tip is swingably supported in the vertical and feed directions,
Feed swing means for swinging the feed arm along the feed direction,
Up and down swing means for swinging the feed arm in the up and down direction,
In a lower feed mechanism of a sewing machine in which an elliptical motion is given to the feed dog by the feed rocking means and the vertical rocking means,
The vertical swinging means has an arm member for transmitting a force according to the principle of leverage, and applies a driving force for vertical swinging to the feed dog via the arm member. Feed mechanism. 2. The lower feed mechanism according to claim 1, wherein the vertical swing means obtains a driving force for reciprocating swing of the arm member from a lower shaft driving a shuttle mechanism of the sewing machine. The vertical swing means is connected to the lower shaft, a driven shaft to which a rotational driving force is applied,
An eccentric cam that is provided on the driven shaft and is driven to rotate and transmits a reciprocating swing driving force to the arm member;
3. The lower feed mechanism according to claim 1, wherein the eccentric cam is provided such that an eccentric position of the eccentric cam with respect to the driven shaft is adjustable. The vertical rocking means applies vertical rocking through a contact member having a contact surface with the feed dog or feed arm,
4. The lower feed mechanism according to claim 1, wherein said contact member is supported so as to be able to change its posture following the vertical swing of said feed dog or feed arm. . 5. An adjusting means for adjusting the height of the feed dog by means of an eccentric pin whose rotation can be adjusted at any one of a fulcrum, a force point and an action point of the arm member. The lower feed mechanism of the described sewing machine.

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